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HOT DEFORMATION AND MARTENSITIC TRANSFORMATION BEHAVIORS OF Fe-32%Ni ALLOY

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 133-138页

作者： j. Huang z. Xu Cold Rolling Mill Baoshan Iron ＆ Steel Co. Ltd Shanghai 201900 China Key Laboratory for High Temperature Materials and Tests of Ministry of Education Shanghai Jiaotong University Shanghai 200030 China

The Hot deformation and martensitic transformation behaviors of Fe-32%Ni alloy was investigated by measurements of electrical resistance and X-ray diffraction. With the increase in strain, the austenite goes through from the work-hardened to the partial dynamcally re-crystallized and then to the completed dynamically re-crystallized. The martensitic transformation characteristics depend on the austenite states. The work-hardening in small strain is helpful to martensitic transformation due to the low dislocation density and little lattice distortion, while the high dislocation density and severe lattice distortion by the increase in strain will hinder the martensitic nucleation. Once dynamic re-crystallization （ DRX ） takes place, the martensitic transformation will be enhanced again, which is related to the heterogeneous dynamic substructures. The growing DRX grain can enhance the martensitic nucleation due to the low dislocation density near its grain boundary.

关键词： Fe-32%Ni alloy hot deformation work hardening dynamic re-crystallization martensitic transformation

家禽红螨(鸡皮刺螨)的杀螨剂抗药性及其管理方法

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养禽与禽病防治 2024年第2期 18-28页

作者： R.z.Abbas D.D.Colwell z.Iqbal A.Khan 刘红(校对) Department of Parasitology University of AgricultureFaisalabad-38040Pakistan Livestock Parasitology Agriculture and Agri-Food CanadaLethbridge Research Centre54031st Ave.S.LethbridgeAB.T1J 4B1Canada Department of Pathology University of AgricultureFaisalabad-38040Pakistan 默沙东动物保健品(上海)有限公司

家禽红螨(鸡皮刺螨)是一种危害养鸡业的吸血害虫,是世界许多地方家禽生产中的重要问题。尽管免疫学、生物技术和遗传学方法取得了进展,但控制家禽红螨却通常仍依赖于合成杀螨剂。随着这些化合物的反复长期使用导致了家禽螨虫抗药性种群... 详细信息

家禽红螨(鸡皮刺螨)是一种危害养鸡业的吸血害虫,是世界许多地方家禽生产中的重要问题。尽管免疫学、生物技术和遗传学方法取得了进展,但控制家禽红螨却通常仍依赖于合成杀螨剂。随着这些化合物的反复长期使用导致了家禽螨虫抗药性种群的形成,可用的有效杀螨剂正在迅速减少。因此需要不断研制新型的化学杀螨剂来取代旧的杀螨剂,但新型杀螨剂的开发和注册是一个漫长且昂贵的过程,故保持和维持现有杀螨剂的有效性至关重要。本综述分为2部分:第一部分提供了对鸡皮刺螨杀螨剂抗药性的基本认识;第二部分提供了关于保持现有杀螨剂有效性的抗药性管理的详细信息。

关键词：家禽红螨杀螨剂杀螨剂抗药性抗药性管理

PREPARATION AND CORROSION RESISTANCE OF NiP/TiO_2 COMPOSITE FILM ON CARBON STEEL IN SULFURIC ACID SOLUTION

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 117-123页

作者： L.z. Song S.z. Song j. zhao School of Environment ＆ Chemical Engineering Yanshan University Qinhuangdao 066004 China School of Materials Science and Engineering Tianjin University Tianjin 300072 China

A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, ESEM （environmental scanning electron microscopy） and EIS （electrochemical impedance spectroscopy） measurements. Results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/L H2SO4 solution. The element valence of the composite film was characterized by XPS （X-ray photoelectron spectroscopy） spectrum, and an anticorrosion mechanism of the composite film was discussed.

关键词： electroless plating and sol-gel composite process artificial neural network NiP/TiO2 composite film corrosion resistance

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深空激光通信研究进展及发展方向(特邀)

激光与光电子学进展 2024年第7期61卷 76-85页

作者：刘超李学莹张开河兰斌代天君鲜浩自适应光学全国重点实验室四川成都610209 中国科学院自适应光学重点实验室四川成都610209 中国科学院光电技术研究所四川成都610209 中国科学院大学北京100049

随着人类对太空的探索日益加深,传统射频通信愈发不能满足高速深空通信的需求,各航天国家先后对深空激光通信技术开展研究。激光通信是实现空间通信的一种重要手段,相比于传统射频通信,激光通信具有通信速率高、终端载荷小、抗干扰能力... 详细信息

随着人类对太空的探索日益加深,传统射频通信愈发不能满足高速深空通信的需求,各航天国家先后对深空激光通信技术开展研究。激光通信是实现空间通信的一种重要手段,相比于传统射频通信,激光通信具有通信速率高、终端载荷小、抗干扰能力强等优点,更适用于超远距离的深空通信。目前,美国进行的研究最多,且已成功实施了两次深空激光通信演示验证。本文针对已有的深空激光通信研究与演示结果进行综述,分析了实现深空激光通信的关键技术,对深空激光通信的发展历程与未来发展进行了探讨。

关键词：深空激光通信激光通信深空探测星际激光通信

A two-scale method for identifying mechanical parameters of composite materials with periodic configuration

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Acta Mechanica Sinica 2006年第6期22卷 581-594页

作者： j.z. Cui X.G. Yu Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 10080 China

In this paper, a two-scale method （TSM） is presented for identifying the mechanics parameters such as stiffness and strength of composite materials with small periodic configuration. Firstly, a formulation is briefly given for two-scale analysis （TSA） of the composite materials. And then a two-scale computation formulation of strains and stresses is developed by displacement solution with orthotropic material coefficients for three kinds of such composites structures, i.e., the tension column with a square cross section, the bending cantilever with a rectangular cross section and the torsion column with a circle cross section. The strength formulas for the three kinds of structures are derived and the TSM procedure is discussed. Finally the numerical results of stiffness and strength are presented and compared with experimental data. It shows that the TSM method in this paper is feasible and valid for predicting both the stiffness and the strength of the composite materials with periodic configuration.

关键词： Two-scale method Stiffness Strength Composite materials Small periodic configuration

基于状态空间模型的激光再制造熔池温度控制系统

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表面工程与再制造 2024年第2期24卷 50-50页

作者： Yang G.-z. Liu T.-M. Song B.-X. jiang X.-Y. Wang z.-S. Chen K.-Q. Liu W.-j. School of Mechanical Engineering Shenyang University of Technology Shenyang China

激光再制造是用于再制造的一项重要技术,在航空航天、冶金、能源等领域应用广泛。然而,形状控制问题一直是制约其规模化和工业化应用的瓶颈。在激光再制造过程中,熔池温度是决定再制造件形状和性能稳定性的关键。基于此,本文提出了一种... 详细信息

激光再制造是用于再制造的一项重要技术,在航空航天、冶金、能源等领域应用广泛。然而,形状控制问题一直是制约其规模化和工业化应用的瓶颈。在激光再制造过程中,熔池温度是决定再制造件形状和性能稳定性的关键。基于此,本文提出了一种基于状态空间模型的激光再制造熔池温度实时在线控制方法,解决了控制机理模型难以建立和多变量约束的问题。

关键词：状态空间模型激光再制造熔池温度航空航天形状控制控制系统变量约束性能稳定性

Decolorization of Direct Black 22 by Aspergillus ficuum

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journal of Environmental Sciences 2001年第4期13卷 472-475页

作者： Dong, X.-j. Du, z.-y. Chen, z. Dept. of Biology/Environmental Sci. Wenzhou Normal College Wenzhou 325003 China

The decolorization of Direct Black 22 by Aspergillus ficuum has been studied. It was found that Aspergillus ficuum could effectively decolorize Direct Black 22 especially when grown as pelleted mycelia. Results showed that the media containing Direct Black 22 at 50 mg/L could be decolorized by 98.05% of the initial color in 24 h. The optimum pH and temperature of decolorization are 4.0 and 33 °C respectively. Aeration was quite beneficial to decolorization. Medium composition and the concentration of Direct Black 22 could affect the rate of decolorization. The dye degraded products assayed by UV-visible spectrophotometer and macroscopic observation showed that the decolorization of Direct Black 22 by mycelial pellets includes two important processes: bioadsorption and biodegradation. The degradation experiment agree with the Michaelis-Menten kinetics equation.

关键词： Bioassay Biodegradation Color Concentration (process) Dyes pH Ultraviolet spectrophotometers

无对比剂预负荷使用和高翻转角动态磁敏感对比灌注加权成像序列可提高对脑淋巴瘤和胶质母细胞瘤的术前鉴别的诊断效能

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国际医学放射学杂志 2024年第1期 131-132页

作者： F.Wang X.F.zhou R.Q.Chen j.Kang X.Y.Yang j.z.Lin 彭景

摘要目的比较扫描前使用和不使用对比剂（CA）预负荷时，高翻转角动态磁敏感对比灌注加权成像（DSC-PWI）序列所获得的相对脑血容量（r CBV）和百分比信号恢复（PSR）,

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z-Score in Fetal Echocardiography–Is there Still Room for New Studies?

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Congenital Heart Disease 2024年第3期19卷 305-314页

作者： Marcio Fragoso Vieira Nathalie jeanne Bravo-Valenzuela Edward Araujo júnior Department of Obstetrics Paulista School of MedicineFederal University of São Paulo(EPM-UNIFESP)São Paulo-SP04023-062Brazil Department of Obstetrics Federal University of Ceará(UFC)Sobral-CE60020-181Brazil Department of Pediatrics Pediatric CardiologySchool of MedicineFederal University of Rio de Janeiro(UFRJ)Rio de Janeiro-RJ21941-853Brazil

Congenital heart disease(CHD)is the most common type of birth defect,representing a significant cause of peri-natal morbidity and *** diagnosis of such anomalies is crucial for improving *** pro-tocols recommend a qualitative assessment of cardiac structures using two-dimensional ultrasound(2DUS)and color Doppler *** cases of suspected abnormalities,quantitative assessments through cardiac structure measurements and reference curves can aid in accurate *** to centiles widely employed in obste-trics,z-scores provide more precise quantification of various cardiac structures,particularly at the extremes of the *** the development of reference curves and z-scores has progressed over the past two decades,a lack of standardization in measurements and statistical methodology for their determination is *** reference curves requires adherence to specific recommendations to improve their *** purpose of this study is to provide a narrative review of the major studies that have generated reference values for cardiac struc-tures using 2DUS and z-scores,to evaluate their methodology,and to provide a summary of the results.

关键词： z-scores reference ranges fetal echocardiography